CVE-2025-40340

CVE-2025-40340 is a security vulnerability that is still awaiting full analysis and scoring. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: drm/xe: Fix oops in xe_gem_fault when running core_hotunplug test. I saw an oops in xe_gem_fault when running the xe-fast-feedback testlist against the realtime kernel without debug options enabled. The panic happens after core_hotunplug unbind-rebind finishes. Presumably what happens is that a process mmaps, unlocks because of the FAULT_FLAG_RETRY_NOWAIT logic, has no process memory left, causing ttm_bo_vm_dummy_page() to return VM_FAULT_NOPAGE, since there was nothing left to populate, and then oopses in "mem_type_is_vram(tbo->resource->mem_type)" because tbo->resource is NULL. It's convoluted, but fits the data and explains the oops after the test exits.

Frequently asked questions

What is CVE-2025-40340?
In the Linux kernel, the following vulnerability has been resolved: drm/xe: Fix oops in xe_gem_fault when running core_hotunplug test. I saw an oops in xe_gem_fault when running the xe-fast-feedback testlist against the realtime kernel without debug options enabled. The panic happens after core_hotunplug unbind-rebind finishes. Presumably what happens is that a process mmaps, unlocks because of the FAULT_FLAG_RETRY_NOWAIT logic, has no process memory left, causing ttm_bo_vm_dummy_page() to return VM_FAULT_NOPAGE, since there was nothing left to populate, and then oopses in "mem_type_is_vram(tbo->resource->mem_type)" because tbo->resource is NULL. It's convoluted, but fits the data and explains the oops after the test exits.
Is CVE-2025-40340 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-40340?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-40340 have an EU (EUVD) identifier?
Yes. CVE-2025-40340 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-201862.
When was CVE-2025-40340 published?
CVE-2025-40340 was published on 2025-12-09 and last updated on 2026-06-17.

References